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severe; strict; rigid; unsparing; relentless
hard (to do); difficult; tricky
intense (e.g. cold); harsh (weather); inclement
宿題が多くて、この先生は厳しいです。
This teacher is strict.
今年の冬は厳しいものになる。
This winter will be harsh.
部活の練習が厳しくて大変だ。
Club practice is tough and exhausting.